1. Field of the Invention
When hydraulic accumulators discharge their working fluid, the dynamic gas/fluid separating device, consisting of a bellows or piston, is placed in a condition of high steady state stress. This stress is due to the force created by the gas pre-charge pressure present or on the side of the separator and the actual lower-working pressure on the expelled fluid side. Further, high point contact loads may exist where the separator mechanically stops on the accumulator vessel structure.
The foregoing conditions must be considered by the designer, especially in high performance driven applications where weight of the unit and operating life are major factors. One factor must be compromised with the other.
2. Description of Prior Art
a) U.S. Pat. No. 2,745,357 introduces an aircraft hydraulic system with an improved pressure type reservoir. PA0 b) U.S. Pat. No. 4,601,369 describes a pressure vessel. PA0 c) U.S. Pat. No. 4,852,615 teaches a hydropneumatic accumulator with two chambers. PA0 d) U.S. Pat. No. 4,959,958 shows a hydraulic pressure system for supplying a fluid under pressure in combination with a gas chamber. PA0 e) U.S. Pat. No. 4,997,009 is an accumulator with metallic bellows and a self-seal mechanism. PA0 f) U.S. Pat. No. 5,009,066 deals with an automotive power steering system. PA0 g) U.S. Pat. No. 5,036,661 shows a regulated level accumulator for liquid under high pressure.